Android笔记之（图片高斯+Glide实现微信图片加载策略+仿微信进度条）
很久以前就想自己实现一下仿微信图片加载的那种策略了，先加载一张模糊的图片，然后再加载清晰大图，今天研究了一下，不过要是Glide支持进度条显示就好了，不得不说Glide很强大，
不啰嗦了，直接上代码了。
首先看看高斯模糊到底怎么实现，你问我我也不会(^__^) 嘻嘻……，直接附上网上的算法：
package com.cisetech.dialogdemo;
import android.graphics.Bitmap;
/** * Author:Yqy * Date:2016-09-29 * Desc: * Company:cisetech */
public class FastBlur {
public static Bitmap doBlur(Bitmap sentBitmap, int radius, boolean canReuseInBitmap) {
// Stack Blur v1.0 from
// http://www.quasimondo.com/StackBlurForCanvas/StackBlurDemo.html
//
// Java Author: Mario Klingemann <mario at quasimondo.com>
// http://incubator.quasimondo.com
// created Feburary 29, 2004
// Android port : Yahel Bouaziz <yahel at kayenko.com>
// http://www.kayenko.com
// ported april 5th, 2012
// This is a compromise between Gaussian Blur and Box blur
// It creates much better looking blurs than Box Blur, but is
// 7x faster than my Gaussian Blur implementation.
//
// I called it Stack Blur because this describes best how this
// filter works internally: it creates a kind of moving stack
// of colors whilst scanning through the image. Thereby it
// just has to add one new block of color to the right side
// of the stack and remove the leftmost color. The remaining
// colors on the topmost layer of the stack are either added on
// or reduced by one, depending on if they are on the right or
// on the left side of the stack.
//
// If you are using this algorithm in your code please add
// the following line:
//
// Stack Blur Algorithm by Mario Klingemann <[email protected]>
Bitmap bitmap;
if (canReuseInBitmap) {
bitmap = sentBitmap;
} else {
bitmap = sentBitmap.copy(sentBitmap.getConfig(), true);
}
if (radius < 1) {
return (null);
}
int w = bitmap.getWidth();
int h = bitmap.getHeight();
int[] pix = new int[w * h];
bitmap.getPixels(pix, 0, w, 0, 0, w, h);
int wm = w - 1;
int hm = h - 1;
int wh = w * h;
int div = radius + radius + 1;
int r[] = new int[wh];
int g[] = new int[wh];
int b[] = new int[wh];
int rsum, gsum, bsum, x, y, i, p, yp, yi, yw;
int vmin[] = new int[Math.max(w, h)];
int divsum = (div + 1) >> 1;
divsum *= divsum;
int dv[] = new int[256 * divsum];
for (i = 0; i < 256 * divsum; i++) {
dv[i] = (i / divsum);
}
yw = yi = 0;
int[][] stack = new int[div][3];
int stackpointer;
int stackstart;
int[] sir;
int rbs;
int r1 = radius + 1;
int routsum, goutsum, boutsum;
int rinsum, ginsum, binsum;
for (y = 0; y < h; y++) {
rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
for (i = -radius; i <= radius; i++) {
p = pix[yi + Math.min(wm, Math.max(i, 0))];
sir = stack[i + radius];
sir[0] = (p & 0xff0000) >> 16;
sir[1] = (p & 0x00ff00) >> 8;
sir[2] = (p & 0x0000ff);
rbs = r1 - Math.abs(i);
rsum += sir[0] * rbs;
gsum += sir[1] * rbs;
bsum += sir[2] * rbs;
if (i > 0) {
rinsum += sir[0];
ginsum += sir[1];
binsum += sir[2];
} else {
routsum += sir[0];
goutsum += sir[1];
boutsum += sir[2];
}
}
stackpointer = radius;
for (x = 0; x < w; x++) {
r[yi] = dv[rsum];
g[yi] = dv[gsum];
b[yi] = dv[bsum];
rsum -= routsum;
gsum -= goutsum;
bsum -= boutsum;
stackstart = stackpointer - radius + div;
sir = stack[stackstart % div];
routsum -= sir[0];
goutsum -= sir[1];
boutsum -= sir[2];
if (y == 0) {
vmin[x] = Math.min(x + radius + 1, wm);
}
p = pix[yw + vmin[x]];
sir[0] = (p & 0xff0000) >> 16;
sir[1] = (p & 0x00ff00) >> 8;
sir[2] = (p & 0x0000ff);
rinsum += sir[0];
ginsum += sir[1];
binsum += sir[2];
rsum += rinsum;
gsum += ginsum;
bsum += binsum;
stackpointer = (stackpointer + 1) % div;
sir = stack[(stackpointer) % div];
routsum += sir[0];
goutsum += sir[1];
boutsum += sir[2];
rinsum -= sir[0];
ginsum -= sir[1];
binsum -= sir[2];
yi++;
}
yw += w;
}
for (x = 0; x < w; x++) {
rinsum = ginsum = binsum = routsum = goutsum = boutsum = rsum = gsum = bsum = 0;
yp = -radius * w;
for (i = -radius; i <= radius; i++) {
yi = Math.max(0, yp) + x;
sir = stack[i + radius];
sir[0] = r[yi];
sir[1] = g[yi];
sir[2] = b[yi];
rbs = r1 - Math.abs(i);
rsum += r[yi] * rbs;
gsum += g[yi] * rbs;
bsum += b[yi] * rbs;
if (i > 0) {
rinsum += sir[0];
ginsum += sir[1];
binsum += sir[2];
} else {
routsum += sir[0];
goutsum += sir[1];
boutsum += sir[2];
}
if (i < hm) {
yp += w;
}
}
yi = x;
stackpointer = radius;
for (y = 0; y < h; y++) {
// Preserve alpha channel: ( 0xff000000 & pix[yi] )
pix[yi] = (0xff000000 & pix[yi]) | (dv[rsum] << 16) | (dv[gsum] << 8) | dv[bsum];
rsum -= routsum;
gsum -= goutsum;
bsum -= boutsum;
stackstart = stackpointer - radius + div;
sir = stack[stackstart % div];
routsum -= sir[0];
goutsum -= sir[1];
boutsum -= sir[2];
if (x == 0) {
vmin[y] = Math.min(y + r1, hm) * w;
}
p = x + vmin[y];
sir[0] = r[p];
sir[1] = g[p];
sir[2] = b[p];
rinsum += sir[0];
ginsum += sir[1];
binsum += sir[2];
rsum += rinsum;
gsum += ginsum;
bsum += binsum;
stackpointer = (stackpointer + 1) % div;
sir = stack[stackpointer];
routsum += sir[0];
goutsum += sir[1];
boutsum += sir[2];
rinsum -= sir[0];
ginsum -= sir[1];
binsum -= sir[2];
yi += w;
}
}
bitmap.setPixels(pix, 0, w, 0, 0, w, h);
return (bitmap);
}
}
由于代码比较少，我就直接全部粘贴了，可以直接拿去研究额。
package com.cisetech.dialogdemo;
import android.app.Dialog;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.widget.ImageView;
import android.widget.ProgressBar;
import com.bumptech.glide.Glide;
import com.bumptech.glide.load.engine.DiskCacheStrategy;
import com.bumptech.glide.load.engine.bitmap_recycle.BitmapPool;
import com.bumptech.glide.load.resource.bitmap.BitmapTransformation;
import com.bumptech.glide.load.resource.drawable.GlideDrawable;
import com.bumptech.glide.request.RequestListener;
import com.bumptech.glide.request.target.Target;
public class MainActivity extends AppCompatActivity {
private int screenWidth;
private ImageView id_iv;
private ProgressBar pb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
WindowManager wm=getWindowManager();
DisplayMetrics outMetrics=new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
screenWidth=outMetrics.widthPixels;
id_iv= (ImageView) findViewById(R.id.id_iv);
pb= (ProgressBar) findViewById(R.id.pb);
Glide.with(this).load("http://img0.bdstatic.com/img/image/shouye/xinshouye/dongman928.jpg")
.centerCrop()
.listener(new RequestListener<String, GlideDrawable>() {
@Override
public boolean onException(Exception e, String s, Target<GlideDrawable> target, boolean b) {
return false;
}
@Override
public boolean onResourceReady(final GlideDrawable glideDrawable, String s, Target<GlideDrawable> target, boolean b, boolean b1) {
Log.e("TAG", "onResourceReady: target-------->"+target );
Log.e("TAG", "onResourceReady: glideDrawable-------->"+glideDrawable );
Glide.with(MainActivity.this).load("http://img0.bdstatic.com/img/image/shouye/xinshouye/dongman928.jpg").
centerCrop().placeholder(glideDrawable).
diskCacheStrategy(DiskCacheStrategy.NONE).
skipMemoryCache(true).dontAnimate().
crossFade(1000).
listener(new RequestListener<String, GlideDrawable>() {
@Override
public boolean onException(Exception e, String s, Target<GlideDrawable> target, boolean b) {
return false;
}
@Override
public boolean onResourceReady(GlideDrawable glideDrawable, String s, Target<GlideDrawable> target, boolean b, boolean b1) {
pb.setVisibility(View.GONE);
return false;
}
}).
into(id_iv);
return false;
}
}).
transform(new MyTransformtion(this)).
diskCacheStrategy(DiskCacheStrategy.ALL).
placeholder(new ColorDrawable(Color.BLACK))
.dontAnimate().into(id_iv);
//createLoadingDialog(this).show();
}
public Dialog createLoadingDialog(Context context) {
LayoutInflater inflater = LayoutInflater.from(context);
View v = inflater.inflate(R.layout.wechat_dialog, null);// 得到加载view
Dialog loadingDialog = new Dialog(context, R.style.loading_dialog);// 创建自定义样式dialog
loadingDialog.setCancelable(false);// 不可以用“返回键”取消
loadingDialog.setContentView(v);// 设置布局
/** * 设置Dialog的宽度为屏幕宽度的61.8%，高度为自适应 */
WindowManager.LayoutParams lp = loadingDialog.getWindow().getAttributes();
lp.width= (int) (screenWidth*0.618f);
lp.height=lp.WRAP_CONTENT;
loadingDialog.getWindow().setAttributes(lp);
return loadingDialog;
}
public class MyTransformtion extends BitmapTransformation{
public MyTransformtion(Context context) {
super(context);
}
@Override
protected Bitmap transform(BitmapPool bitmapPool, Bitmap bitmap, int i, int i1) {
Log.e("TAG", "transform: bitmap-------->"+bitmap );
return FastBlur.doBlur(bitmap,10,true);
}
@Override
public String getId() {
return "com.cisetech.dialogdemo.MyTransformtion";
}
}
}
仿微信进度条可以看我另外一篇博客Android进阶之（Dailog详解），这里写在一个工程里面了，我就直接贴代码了。
源码链接：http://pan.baidu.com/s/1gflwaFx